I have a Gigabyte GA-8AENXP-D Mobo. I just installed 2 more Kingston 1gb DDR2 modules for a total of 4 kingston 1gb DDR2 modules. When it boots it only sees 3145728k of ram. When I had just 2 1gb modules it showed 2091752bytes of ram. I know the new ram is good as I have replaced the old modules with the new ones and everything worked fine.

I can even remove one of the modules and still get the bios reporting it only sees 3145728bytes of ram. I have the modules in the correct slots. I have the latest bios update from Gigabyte. And this Mobo is supposed to be able to handle 4 gigs of ram.

Because of this, windows will only use the 3 gigs of ram!

Anyone come across something like this before?

Thanks.

first off, i'd like to point out that running 4 gigs of non-ecc ram and/or using all 4 memory slots is a bad idea. reliability and performance take a big hit, one that often negates the advantages of more ram.

you should proceed to test out all your modules one at a time, then trying them in dual channel config. a little experimenting with module setups will often reveal the bad stick/problem. just remember to be smart and avoid killing your machine with static discharge.

Thanks for pointing out some of the obvious issues that could be at work here.

But, as I posted in the originating thread, the ram sticks test out fine in the same mobo. This is not an issue with the ram sticks themselves.

I have tried every concievable slot combination in the "6" slots that this mobo has. This is double sided ram and conforms with this particular boards requirements according to the supplied documentation. And there are no updates to this documentation on the Gigabyte site.

And still the bios can only see three of the ram sticks. If I reduce the ram from 4 sticks to 3 sticks the bios reports the same 3145728k of ram as it did with the 4 sticks installed. Which would lead one to suspect a ram module, but again, if I put both new sticks in the mobo and remove the 2 old sticks the bios properly sees 2097152k of ram. Proving that the ram itself is not the issue.

Any other ideas?

Thanks.

Ok, I haven't figured this out yet, so I sent an email to the Gigabyte support site.

Hopefully they will get back to me before the end of the year! :rolleyes:

Ok, here is the first answer from the official Gigabyte technical assistance dweebs.


Answer : Hi,

Due to standard PC architecture, a certain amount of memory is reserved for system usage and therefore the actual memory size is less than the stated amount. For example, 4GB of memory size will instead be shown as 3.xxGB memory during system startup.

Here is my reply:

Question : I would appreciate it if you would not give me "canned" replies out of the owners manual for this mother board.

I already know about the "limitations of the PC architecture". I should still see more than
3145728K of memory with 4 gigs of memory installed on this board! Are you trying to tell me that the PC architecture will reserve almost a full gigabyte of memory for system usage? I think not.

If you took the time read my original question, you would have seen that if I remove one of the 1gig memory modules from the mother board, the bios still sees only 3145728K
of total memory.

This causes Windows XP to only see 3 gigs of memory! If it can see only 3 gigs of memory, then it can only use 3 gigs of memory.

There are other motherboards on the market that do allow Windows XP to see 4 gigs of memory, why can't yours?

I would like to know if there is a way to escalate this trouble shooting process. A phone number I can call perhaps? My dime no problem!

Or is there an actual persons email address I can use to correspond?

This mother boards inability to utilize only 3 gigs of memory is very troubling.


This beyond pathetic if this is the best they can do!

perhaps you should check out your sticks in another system (a local pc repair shop could do the testing easily). if they check out OK, and you're certain that the board should be yielding 4gigs, then your board is probably shot. keep in mind that the memory controller for your system lies within the AMD processor itself, so that is another aspect to the problem.

I'm also having the same problem and I'm using a differnt mobo.
asus a8n sli deluxe, 4gb ocz ram, windows xp sp2.
bios shows 4gb but windows only shows 3gb

Is this a windows issue or mobo issue?